INDIANAPOLIS — Saquon Barkley might not care if he's the first, fifth or last pick of the NFL draft, but at the NFL combine on Friday the Penn State running back solidified his stock as one of the best players available at any position.

Barkley turned in an impressive workout on the first day of field drills, running a 4.4-second 40-yard dash that was second best among running backs and posting a 41-inch vertical jump.

"I’m competitive, but I don’t care if I’m drafted one, five or 72 or the last pick," Barkley said Thursday. "I’m going to come in with my head low ready to work. That’s not going to change me. No matter where I’m drafted or who I’m drafted by, they’re going to get the same person."

Barkley is widely projected as a top-five pick in a deep group of running backs, and he wasn't the only standout at his position in drills Friday.

Auburn running back Kerryon Johnson, a potential second-round choice, and Alabama's Bo Scarborough, both posted 40-inch verticals, tied for second behind Barkley — just four running backs have topped 40 inches in the past three years, including Ameer Abdullah and Zach Zenner.

Asked Thursday what message he was trying to convey to teams at the combine, Guice, a potential first-round pick and someone who could interest the Lions with the 20th pick of the first round, said, "If you don’t draft me I’m going to give your defense hell."

USC running back Ronald Jones, another potential Lions' target in Round 1, pulled up with a hamstring injury on his only 40-yard dash attempt.

Michigan's Mason Cole tied for 13th among offensive linemen with a 5.23-second 40.